ANENQUIRYCONCERNINGHUMANUNDERSTANDING(SECTIONVII) 711
the different events, in the same proportion as they have appeared in the past, and conceive
one to have existed a hundred times, for instance, another ten times, and another once. As
a great number of views do here concur in one event, they fortify and confirm it to the
imagination, beget that sentiment which we call belief, and give its object the preference
above the contrary event, which is not supported by an equal number of experiments, and
recurs not so frequently to the thought in transferring the past to the future. Let any one try
to account for this operation of the mind upon any of the received systems of philosophy,
and he will be sensible of the difficulty. For my part, I shall think it sufficient, if the pre-
sent hints excite the curiosity of philosophers, and make them sensible how defective all
common theories are in treating of such curious and such sublime subjects.
SECTIONVII. OF THEIDEA OFNECESSARYCONNEXION
PARTI
The great advantage of the mathematical sciences above the moral consists in this, that the
ideas of the former, being sensible, are always clear and determinate, the smallest distinc-
tion between them is immediately perceptible, and the same terms are still expressive of
the same ideas, without ambiguity or variation. An oval is never mistaken for a circle, nor
an hyperbola for an ellipsis. The isosceles and scalenum are distinguished by boundaries
more exact than vice and virtue, right and wrong. If any term be defined in geometry, the
mind readily, of itself, substitutes, on all occasions, the definition for the term defined: Or
even when no definition is employed, the object itself may be presented to the senses, and
by that means be steadily and clearly apprehended. But the finer sentiments of the mind,
the operations of the understanding, the various agitations of the passions, though really in
themselves distinct, easily escape us, when surveyed by reflection; nor is it in our power
to recall the original object, as often as we have occasion to contemplate it. Ambiguity, by
this means, is gradually introduced into our reasonings: Similar objects are readily taken
to be the same: And the conclusion becomes at last very wide of the premises.
One may safely, however, affirm, that, if we consider these sciences in a proper
light, their advantages and disadvantages nearly compensate each other, and reduce both
of them to a state of equality. If the mind, with greater facility, retains the ideas of geom-
etry clear and determinate, it must carry on a much longer and more intricate chain of
reasoning, and compare ideas much wider of each other, in order to reach the abstruser
truths of that science. And if moral ideas are apt, without extreme care, to fall into obscu-
rity and confusion, the inferences are always much shorter in these disquisitions, and the
intermediate steps, which lead to the conclusion, much fewer than in the sciences which
treat of quantity and number. In reality, there is scarcely a proposition in Euclid so sim-
ple, as not to consist of more parts, than are to be found in any moral reasoning which
runs not into chimera and conceit. Where we trace the principles of the human mind
through a few steps, we may be very well satisfied with our progress; considering how
soon nature throws a bar to all our enquiries concerning causes, and reduces us to an
acknowledgment of our ignorance. The chief obstacle, therefore, to our improvement in
the moral or metaphysical sciences is the obscurity of the ideas, and ambiguity of the
terms. The principal difficulty in the mathematics is the length of inferences and com-
pass of thought, requisite to the forming of any conclusion. And, perhaps, our progress in